any force responsible for maintaining an object on a curved path around a fixed center. In introductory coursework this is usually "uniform circular motion" and yields several simple and useful relations. Not to be confused with the centrifugal pseudo-force experienced in a accelerated referenced ...

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32 views

Which centripetal force equation should I use for centripetal motion in uniform magnetic field, and why?

So far I learn two equations, doing the same thing: $$F_c = m\frac{v^2}{r} = qvB$$ It leaves me undecided when a question asks "by what factor is the force increased when velocity is double". The ...
7
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4answers
1k views

Will the sea form a concave surface?

Without neglecting the fact that the earth is rotating, let us be in a ship (such that there is no relative motion between sea and ship) in a sea that surrounds the northern most or southern most ...
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1answer
36 views

Centrifugal force on objects rotating around Earth

Suppose two objects travel around the equator on Earth at the same speed, $v$, in opposite directions, where the speed $v$ is measured relative to the Earth's surface. Will they experience different ...
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5answers
174 views

Why does solving $\mu mg = m \frac{v^2}{r}$ give the *max* possible velocity?

So here is the standard problem setup of a car turning on an unbanked road: A 1000 kg car is going around a curve with radius 30 meters. If the coefficient of friction between the car's tires ...
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2answers
92 views

Intuitive explanation for why centripetal acceleration is $\frac{v^2}{r}$

There are several ways to write centripetal acceleration $$\frac{v^2}{r} = \omega^2 r = v \omega$$ Are there intuitive explanations for any of these three forms? For instance, I can sort of explain ...
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3answers
66 views

Deriving escape velocity using centripetal force

Recently started book on gravity and there (not only there, it is correct way) the escape velocity was given as $${v_{esc}=\sqrt{\frac{2GM}{R}}}.$$ I wanted to derive this myself and I decided to use ...
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3answers
122 views

Shape of a rotating fluid surface

I was going through fluid dynamics and I came upon this section on the shape of a liquid surface in a rotating cylindrical vessel. The working in the book is something like this: It considers a mass ...
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2answers
38 views

Electron moving in constant magnetic field

I'm revisiting an old problem which is to show that the trajectory of an electron in a constant magnetic field $\textbf{B} = (0,0,B)$ is a helix. I started with the Lorentz force equation $$ ...
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1answer
52 views

The physics behind tilting trains

So I'm trying to get an intuition behind the physics behind banked curves (and tilting trains). I know how to do the calculations, but I'm still struggling with the "why". If I'm sitting in a train, ...
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2answers
79 views

If the velocity of an object, rotating on a vertical circle, at the topmost point is zero, how can it loop the whole circle?

Normally, if a body is attached to a string & is rotated in a vertical circle, then to loop the whole circle, the rope must not slack at the topmost point & there should be a velocity for ...
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0answers
33 views

How to prove by symmetry that tension in a section of rapidly rotating wheel act tangentially?

Suppose a thin uniform wheel of radius $r$ is rotating rapidly about its axis; its spokes have almost negligible strength. According to the book, the centripetal force is provided by the tension ...
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2answers
81 views

Why can this question about Centripetal Force not be answered in this way?

Here is the question: "A car travels round a bend which has radius $100 m$ and is banked at an angle of $20°$ to the horizontal. The car is travelling at a speed of $30 ms^{-1}$. What is the least ...
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1answer
111 views

Moving Around Space Without Propellant [closed]

A mechanism as shown in following picture is floating freely in space. Concentrating on the main components first, which is the long rod in the middle with another 8 smaller rods connected to it, ...
0
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0answers
27 views

Need clarification for Relation between angular momentum and centripetal force

I've recently started studying angular momentum, so, as far as I understand, angular momentum is conserved as long as any form of centripetal force can be maintained in the new system or otherwise it ...
2
votes
1answer
73 views

Coefficient of friction on a loop-the-loop!

Here is a question that I thought of while doing a physics lab in class. We dropped a marble from a certain height down a ramp and around loop-the-loop and let it fly off of a table and then we were ...
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2answers
63 views

What forces are applied as a car exits a curve with constant speed?

Imagine a car taking a curve with constant speed. Assuming no friction or air resistance all we would have would be centripetal force. As the car's front wheels straighten to exit the curve the ...
2
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4answers
414 views

What causes a car's velocity to follow the front wheels' direction?

I'm trying to simulate a car with correct physics models. In this example we let the car have a constant speed, and there are no forces (friction and drag) to slow down the speed. Here's a video that ...
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1answer
35 views

Force responsible for increasing a spiraling object's tangential velocity

Suppose we have a small mass attached to a string that has been fed through a hole in the friction-less table on which the mass is rotating. Pulling the string downwards thus decreases the radius of ...
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1answer
63 views

Gravitational Force vs. Centripetal Acceleration

Can someone please explain this conceptually: Suppose we have two probes, one one the surface of the earth and one in geosynchronous orbit. Since $a_c = \omega^2r$, the probe that is further out, ...
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1answer
31 views

Angular and linear displacement of a turning car

My illustration is supposed to show a simplified car (with just two wheels, where the front wheel has been rotated $-90 \text{ degrees}$). Let the car travel at constant speed. This means that the ...
0
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1answer
48 views

Finding radius of turning car to calculate the centripital force

I'm writing a program to simulate a car driving. I'm wondering how I should find the radius when calculating the centripital force. If we let the car travel at a constant speed, then $F_{net} = ...
6
votes
8answers
2k views

Is there a huge difference between centrifugal and centripetal forces?

I am doing a video for 8th grade on the subject. I'm showing the experiment of swinging a bucket of water over your head. Is there a huge difference between centrifugal and centripetal forces? Would ...
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0answers
39 views

How realistic is a “bolas” system for artificial gravity in space travel?

The spinning space-station is very popular in sci-fi as a means of emulating gravity in space. But it requires rather a large diameter to minimise "gravitational gradient" effects and that means such ...
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3answers
134 views

Is the planet Mesklin as described in Hal Clement's Mission of Gravity correct?

The book Mission of Gravity describes a planet with a mass of 16 times Jupiter spinning at a rate of one revolution every 17.75 minutes. This causes it to stretch out into an oblate spheroid and has ...
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0answers
31 views

Why isn't $g$ larger on the equator? [duplicate]

I understand that at the equator, you will have maximum centripetal force acting on you, whereas if you're standing directly on the pole you will have none. But because centripetal is a resultant ...
0
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2answers
120 views

What guarantees that in a circular motion in a vertical loop, the resultant of the forces will always point to the center?

Here's what I know: If a body moves in a circular trajectory, then the resultant of all the forces must point to the center of the circle it describes in its movement. If a body moves in a vertical ...
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2answers
101 views

Question about a car on a banked turn with no friction

A popular physics page explaining how a car can make a banked turn even with no friction : gives the following free body diagram and then says In the vertical direction there is no ...
2
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0answers
37 views

The athlete feels a centrifugal force when whirling the hammer - is there always a centrifugal force associated with a centripetal force? [closed]

(this is a homework question) To this, I would say that the centrifugal force is just the reactionary force of the centripetal force, which is causing the hammer to 'want' to move away. Therefore, ...
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1answer
39 views

Why do objects experiencing centripetal acceleration not end up at their centers?

A satellite rotates around the earth; a ball on a string rotates around my hand. Each of these things experiences a net force equal to $ mv^2/r = F_{centripetal}$. Why does no object end up at the ...
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1answer
126 views

Calculating the first cosmic velocity / velocity for a circular orbit

Today in class we calculated first cosmic velocity using this equation $$G\frac{mM}{(R+h)^2}=\frac{mV^2}{R+h},$$ where $m$ = mass of the body, $M$ = mass of the Earth, $R$ = radius of the Earth, $h$ = ...
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votes
1answer
62 views

Is there a difference between normal forces and centripetal forces?

Is there a difference between normal forces and centripetal forces? Or they just mean the same thing? My textbook talks about centripetal forces, but not about normal ones.
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4answers
298 views

Question about magnetic force

I have some confusion regarding the magnetic force. I know that the magnetic field created by a moving charge or current EXERTS a force on any moving charge or current that is present in the field. ...
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1answer
54 views
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3answers
150 views

Does circular motion cause centripetal force OR does centripetal force cause circular motion?

Does circular motion cause centripetal force, or does centripetal force cause circular motion, or are they both occurring hand in hand together instantaneously? One more question: If I project a body ...
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2answers
137 views

Question about circular motion of car turning

When we move round a roundabout there is a frictional force between the tires and the road that acts towards the centre of the roundabout in order to produce the circular motion. Why then do we ...
1
vote
0answers
67 views

Motion in a vertical circle and forces in polar coordinates

Suppose a particle with mass $m$ is whirled at instantaneous speed $v$ on the end of a string of length $R$ in a vertical circle. Let $\theta$ be the angle the string makes with the horizontal. I know ...
2
votes
1answer
53 views

Centrifugal Term

I'm studying quantum mechanics with Griffiths (2 nd edition) and I have one question related to the Schrodinger equation in spherical coordinates. In the radial equation: ...
0
votes
1answer
172 views

How does frequency change with centripetal force?

Using the equation $$F_c = {{mv^2}\over{r}}$$ I can see that mass and velocity are directly proportional to centripetal force. I can also see that the radius length is inversely proportional to ...
0
votes
2answers
89 views

A simple pendulum

The idealized simple pendulum model (see the following figure) assumes that at every point of time the string to which the bob is attached exerts an equal and opposite force on the bob as does the ...
0
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2answers
50 views

Given the radius and angle of a frictionless banked curve, is it possible to find centripetal force?

A car is driving on a frictionless banked curve of radius 45 metres and 25 degrees. Is it possible to find centripetal force? If not possible, explain why.
2
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1answer
39 views

Tension of a curled chain, connected with understanding the chain fountain

I'd like to understand the physics of a chain fountain (https://www.youtube.com/watch?v=_dQJBBklpQQ) and in order to do so, I am reading this paper credited for solving the mystery: ...
1
vote
1answer
67 views

Wheel slowing down with constant acceleration

A wheel of radius $R$ spins about its center with a centripetal acceleration of $v^2/R$. I get that the acceleration at all points on the rim of the wheel point towards the center of the wheel. But, ...
0
votes
1answer
79 views

Finding the centripetal force at any random point in a wheel which is rotating as well as translating

If we have a wheel which is decelerating due to friction with acceleration $-A$ and angular acceleration $-\alpha$, and we want to find the acceleration at any point, then we can simply find it using ...
0
votes
1answer
31 views

A question on tangential and centripetal accelerations?

What is the proof that the component of acceleration perpendicular to motion for all motion is $v^2/r$, where r is the radius of curvature? Also, what is the proof that the component of acceleration ...
1
vote
1answer
40 views

Circular motion normal force

Extracted from this article (see the bottom section): Some roller-coasters have loop-the-loop sections, where you travel in a vertical circle, so that you're upside-down at the top. To do this ...
0
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1answer
158 views

Clearing up confusion about orbital mechanics

When I see an orbital mechanics problem, I recall the following things from my "toolbox": Angular momentum is conserved for a body orbiting a planet, since the torque due to gravity is 0. Kinetic ...
0
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1answer
88 views

max speed of circular motion

I understand that it is the static friction force that lets us turn the car around the corner. It provides the necessary centripetal acceleration. Static friction opposes the impending motion of the ...
0
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1answer
18 views

Can I apply centripetal force

Suppose you have some object moving near a large planet. We can use energy conservation to obtain $K+U$ is constant. Also $F_c=F_g$, (I believe we can apply this even though we are not moving in a ...
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0answers
60 views

Centripetal acceleration for a polyline

This question is also posted on the Mathematics forum. I am not physicist, therefore sorry if my question is a bit primitive. Given a polyline (x and y coordinates) in Cartesian coordinate system, ...
2
votes
3answers
381 views

Centripetal force in this example?

I have a general question regarding the centripetal force. In the example of a ferris wheel where there is a normal force pushing up against the person and the gravitational force pulling the person ...